Brake releasing apparatus



June 26, 1945. R. T. WHITNEY BRAKE RELEASING APPARATUS Filed Dec. 23, 1943 INVEN'I'OR RALPH T WHITNEY A TTORNE Y I I Patented June 26, 1945 BRAKE RELEASING APPARATUS Ralph T. Whitney, Irwin, Pa., assignor to The Westinghouse Air Brake Company, Wilmerding, Pa., a corporation of Pennsylvania Application December 23, 1943, Serial No. 515,364

14 Claims.

This invention relates to fluid pressure brake apparatus of the automatic type and more particularly to means for causing operation of said apparatus to effect a release of the brakes.

When a car equipped with automatic brake apparatus and having the reservoir or reservoirs thereof charged with fluid under pressure is cut out of a train and the brake pipe on the car is vented, the brake controlling valve device will, as a result of such venting, move to emergency position. Movement of the brake controlling valve device to emergency position establishes communication between the reservoir or reservoirs and the brake cylinder device and permits the fluid in said reservoir or reservoirs to equalize into the brake cylinder device to effect an emergency application of the brakes on the car.

When releasing a brake application thus effected, the usual practice has been for a trainman to operate the reservoir release valve or valves to completely dissipate the fluid pressure from the reservoir or reservoirs and thereby from the connected brake cylinder device to release the brakes. This operation not only Wastes the stored fluid pressure in the reservoir or reservoirs but also requires time on the part of the trainman since he must hold the reservoir release valve or valves open until the brakes are released. When a car is subsequently placed in a train, it is then necessary to completely recharge the reservoir or reservoirs either by a local yard charging plant or by a coupled locomotive before the train may be moved. This requires a relatively long period of time and consequently excessive use and wear of apparatus to accomplish same, all of which is undesirable.

From the foregoing it will be understood that it is undesirable to dissipate the stored fluid pressure in the reservoir or reservoirs to effect a release of the brakes when the car it cut out of a train, and one objectof the invention is the provision of novel brake release meansfor accomplishing this result.

'According to the invention this object is attained by brake release means, which, though not limited in use to any specific triple valve or the like, is particularly arranged for attachment to the pipe bracket of the well known AB valve. This brake i lease means embodies a slide valve having a normal position opening communication between the brake pipe on the car and the brake pipe passage in the AB valve, a second position for closing said communication and for connecting the auxiliary reservoir on the car to the brake pipe passage in the AB valve and a pressure from the'brake cylinder device to the atmosphere, thereby eifecting a release of the brakes on the car. The slide valve of the release-means is operable manually from said normal position to said second position and is automatically operative from the second position to said third position in which latter position it will remain until the brake pipe on the car is recharged, as after the car is again cut into a train, at which time the pressure of fluid supplied to the brake pipe will automatically reset or actuate the slide valve of the release means from the third position back to its normal position to reconnect the AB valve to the brake pipe, so that said valve may then be controlled from the brake pipe, in the usual manner.

Other objects and advantages will be apparent from the following more detailed description of the invention.

In the accompanying drawing the single'figure is a diagrammatic view of an B brakeequipment having associated therewith brake release means embodying the invention.

Description As shown in the drawing, the brake equipment comprises an AB valve l embodyin a pipe bracket 2, a service portion 3 mounted on one face of said bracket, an emergency portion 4 mounted on another face of said bracket, and other parts which while shown in elevation, do not enter into the invention and'will not therefore be described. The brake equipment further comprises the usual auxiliary reservoir 5, emergency reservoir 6, brake cylinder device 1 and, according to the invention, the brake releasing valve device 8 arranged for attachment to the pipe bracket 2.

The service portion 3 comprises a piston 'l having at one side a piston. chamber II which is normally in communication with a brake pipe I-2 by Way of a passage l3 and through the brake releasing valve device 8, as will be hereinafter described. At the opposite side of piston I0 is a valve chamber l4 in constant communication with the auxiliary reservoir 5 by way of a passage and pipe I 5, a branch of said passage extending to the brake releasing valve device 8. The valve chamber [4 contains a slide valve 11 and an auxiliary slide valve l8 arranged for control by the piston In in the usual manner.

When the brake pipe l2 and piston chamber I I are charged with fluid under pressure, and piston I is in its brake release position as shown, fluid will flow from said piston chamber through a feed groove I9 around said piston to valve chamber I4 and thence through passage and pipe to the auxiliary reservoir 5 to charge same to the same pressure as that in the brake pipe. With piston l0 and slide valves 11. and I8 in release position, fluid under pressure flows from valve chamber l4 through a port in the main slide valve to a passage 2|, and thence to a connected passage 2m. Fluid under pressure thus supplied to passage 21a flows :to the emergency reservoir 6 by way of a connected passage and pipe 2"; for charging said reservoir to brake pipe pressure. Also in the release position of the main slide valve ll the brake cylinder is open to .the atmosphere through a pipe 22, passage 23, past check valve 24 in the emergency portion 4 of the control valve device I, and thence through passages 25 and 26, a cavity 26a in said slide valve and a release passage :21.

Upon a reduction in pressure in brake pipe l2 and thus in piston chamber H at either a service or an emergency rate, the piston I0 is adapted to move into sealing engagement with a gasket 28 which is clamped between the pipe bracket 2 and the casing of the service portion 3. During such movement the piston first. shifts the auxiliary slide valve l8 relative to the main slide valve H to a position lapping port 20 and opening a service port 29 to the valve chamber-i4, and then shifts both slide valves in unison to a position in which the brake cylinder passage 26 is disconnected from the release "passage 21 and in which the service port 23 registers with passage 26. Fluid under pressure then flows from the auxiliary reservoir 5 to the brake cylinder device 1 and actuates same to apply the brakes on the vehicle.

Upon a subsequent increase in brake pip pressure for effecting. a release of brakes, the piston 13 and slide valves 11 and l8 are returned to their normal position in which they are shown and in which the auxiliary reservoir 5 is supplied with fluid from the brake pipe by way of feed groove I9 and from the emergency reservoir 6 by way of port 20 until substantial equalization of the pressures in both auxiliary-and emergency reservoirs occurs, when both reservoirs charge to the normal pressure in the brake pipe as before described.

Also in this position of the main slide valve I! the brake cylinder device I is disconnected from the auxiliary reservoir 5 and opened to the atmosphere for releasing the brakes.

The emergency valve portion 4 comprises an emergency piston 32 having at one sidea chamber 33 which is normally open to the brake pipe by way of passage l3 and the brake releasing valve device 8, and having at the opposite side, a valve chamber 34 open to a quick action chamber 35.

The valve chamber 34 contains a main slide valve 36 and an auxiliary slide valve 31 mounted on the main slide valve, the two slide valves being connected for movement by piston 32 in the usual manner.

When the brake pipe l2 and thereby the emergency piston chamber 33 are charged with fluid under pressure, the emergency piston 32 and slide valves 36 and 31 will occupy their normal position, in which they are shown. With the slide valve in this position, a feed port 38 is open to piston chamber 33 for supplying fluid under pressure from the brake pipe to valve chamber 34 and quick action chamber to charge same with fluid at the same pressure as in the brake pipe.

Upon a service reduction in pressure in piston chamber 33, in response to a service reduction in brake pipe pressure, the emergency piston and thereby the auxiliary slide valve 31 will move in the direction of said chamber to a position in which a port .39 in the auxiliary slide valve registers with a port 40 in the main slide valve, and through these registering ports fluid will then flow from the valve chamber and quick action chamber 35 to a passage 4| and thence to the atmosphere. This release of fluid under pressure from the valve chamber 34 and quick action chamber 35 will reduce the pressure in said chambers at the same rate as the brake pipe pressure acting on the opposite side of the piston 32 reduces upon a service rate of reduction in brake pipe pressure,

so as to thereby stop movement of the piston 32 in the service position.

The venting capacity of ports 39 and 46 however is insufllcient toreduce the pressure of fluid in valve chamber 34 as fast as the brake pipe pressure in piston chamber 33 reduces upon an emergency rate .of reduction in brake pipe pressure, so that upon such a reduction, a diflerential is obtained between the pressure in piston chamber 33 and valve chamber 34 of such a degree as to cause said piston to move to an emergency position into engagement with-a gasket 42 which is clamped between the pipe bracket 2 and the casing of the emergency portion 4. The emergency piston as it thus moves will shift the main slide valve 36 to' an emergency position in which a passage 43 is opened to valve chamber 34. Fluid under pressure will then flow from valve chamber 34 and quick action chamber 35 to passage 43 and thence to a chamber 44 for actuating a piston 49 to unseat a brake pipe vent valve 45 past which a sudden quick venting of fluid under pressure from the brake pipe l2 then occurs by way of a passage Ill. The fluid pressure in valve chamber 34 and quick action chamber 35 will then be gradually dissipated through a port 46 in piston 49 to permit closure of the vent valve 45 aftera certain lapse of time.

In emergency position of the main slide valve 34 a cavity 41 therein connects the emergency reservoir passage 2la to passage 26 which upon an emergency reduction in brake pipe pressure is supplied with fluid under pressure from the auxiliary reservoir 5 by operation of the service application valve device 3 as hereinafter described.

Fluid under pressure from both the auxiliary and emergency reservoirs will thus be supplied to passage 26 upon an emergency reduction in brake pipe pressure and such fluid will initially flow past check valve 24 to the brake cylinder device 1. The check valve 24 is arranged to close upon an increase in brake cylinder pressure following which further flow of fluid to the brake cylinder device will occur through a choke 43 and finally by way of a timing check valve 48a which also opens as is well known, Thus an emergency application of the brakes is effected.

This specific control of the flow of fluid from the two reservoirs to the brake cylinder device is immaterial to the present invention and a further description thereof is not deemed essential, since it is merely desired to bring out that upon an emergency reduction in brake pipe pressure, the auxiliary reservoir 5 is placed in communication with the brake cylinder device 1 by operation of the service valve portion 3, and the emergency reservoir 6 is placed in communication with the brake cylinder device by operation of the emergency valve device 4, and the fluid pressure in both of said reservoirs is therefore permitted to equalize into the brake cylinder device to effect the emergency application of the brakes.

It is also desired to bring out that after an emergency application of the brakes is completed, the brake pipe l2, emergency valve chamber 34, and quick action chamber 35 will be at atmospheric pressure so that the emergency slide valve 36 will remain in its emergency position. The parts of the service application valve device will also remain in their application position with the brake pipe completely vented since the service Piston is subject at this time in valve chamber M to the pressure of fluid in the auxiliary reservoir 5 which will be equalized with that in the emergency reservoir into the brake cylinder device 1 at a value such as sixty pounds, assuming the brake pipe pressure preceding the emergency reduction was seventy pounds. Thus at the termination of an emergency application of brakes the service piston ID will be held in emergency position by auxiliary reservoir pressure, while the emergency piston will be subject on opposite sides to fluid at substantially atmospheric pressure.

In order to release an emergency application of the brakes, fluid under pressure will be supplied to the brake pipe l2 and thence to piston chambers H and 33for increasing the pressure of fluid acting on the service and emergency pistons l and 32, respectively. Upon a slight increase in the pressure of fluid in chamber 33 the emergency piston 32 will move out of its emergency position and back to its normal position which is defined by its contact with a plunger 5| which is subject to the pressure of a spring 52. The piston 32 as it is thus moved will shift the main slide valve 36 back to its normal position in which passage 2| from the emergency reservoir 6 is lapped, thereby closing communication between said reservoir and passage 26. which passage 26 at this time is still open to the brake cylinderdevice 'l and to the auxiliary reservoir 5 by way of the service valve portion 3.

Also in the normal position of the emergency piston 32, the port 38 is open to chamber 33. so that fluid will then flow from the brake pipe to valve chamber 33 and the quick action chamber 35 for charging same. The rate of increase in brake pipe pressure for releasing the brakes sufilciently exceeds the rate of charging of the valve chamber 34 by way of feed port 38, as to provide a faster increase in pressure in piston chamber 33 than occurs in valve chamber 34, so that by the time the brake pipe pressure acting in chamber 33 is increased to a relatively low degree, such as ten pounds, a sufficient differentialin pressure will be provided on piston 32 to overcome the pressure of spring 52 on plunger 5| and move the piston 32 past its release position to a back-dump position defined by contact between said piston and a stop 53 in the casing.

In this back-dump position of the main slide valve 36, the cavity 41 opens communication between passage 26 and a passage 54 and fluid under pressure from the brake cylinder device I and connected auxiliary reservoir 5 will flow to passage 54 and thence past two serially arranged check valves 55 toa passage 56 which is open to the brake pipe I2. Since the emergency brake applying pressure in the brake cylinder and auxiliary reservoir may be around sixty pounds-as hereinbefore mentioned and the pressure of fluid in the brake pipe I 2 may be at a'relatively low degree, such as ten pounds at the time the emergency valve moves to back-dump position, the fluid from the brake cylinder device I and connected auxiliary reservoir supplied to the brake pipe will therefore cause a, local increase in pressure therein to about forty-five pounds, thus hastening the recharge of the brake pipe l2 and thereby the release of brakes following an emergency application. Upon substantial equalization of the pressure of fluid inthe brake cylinder device I and auxiliary reservoir 5 into the brake pipe |2, the upper check valve 55 will seat under the action of a sprin 51 to prevent back flow of fluid from the brake pipe upon a further normal increase in brake pipe pressure back to its normal value. During this further increase in brake pipe pressure the valve chamber 34 and quick action chamber will become charged to the same pressure as in the brake pipe by way of feed port 7 38. Upon substantial equalization of these pressures spring 52 acting on plunger 5| will return the emergency piston 32 and the slide valves3|i and 3! to their normal positions. I When the brake pipe pressure effective in chamber H of the service portion 3 is increased to a degree slightly exceeding the reduced auxiliary reservoir pressure in valve chamber l4 said piston will operate to return the slide valves l"! and I8 to their normal release position in which they are shown, in which position, communication is closed between the brake cylinder device I and the auxiliary reservoir 5 and said reservoir is'recharged with fluid under pressure from the brake pipe, and the brake cylinder device is opened'to atmosphere for releasing the brakes. position of the slide valve H, the emergency 'reservoir G isagain opened to valve chamber l4 and is therefore recharged with fluid at the pressure in the brake pipe. j

Briefly summarizing the operations above described fora clear understanding of the operation of the reservoir releasing valve device 8 which follows, it will be noted that upon an emergency reduction in brake pipe pressure from a normal degree such as seventy pounds, both the auxiliary reservoir 5 and emergency reservoirfi are opened to the brake cylinder device I and the pressures of fluid in said reservoirs equalize into said brake cylinder device at substantially sixty pounds. Upon a subsequent increase in brake pipe'pressure to efiect a release of the emergency brake application, the several parts of the emergency valve device 4 move to back-dump position upon a relatively small increase in brake pipe pressure to disconnect the emergency reservoir from the brake cylinder device 1. thereby holding in the emergency reservoir fluid at substantially sixty pounds pressure. In this back-dump position the pressure of fluid in the brake cylinder device I, auxiliary reservoir 5 and brake pipe I2 equalize at substantially forty five pounds which results in a reduction in pressure in said reservoir and brake cylinder device to about forty-five pounds. When the brake pipe pressure is then increased above this pressure (forty-five pounds) effective in the auxiliary reservoir, the piston I0 and slide valves l1 and |8 are returned to their normal position. With the'slide valves in this position,

Also in this communication isclosed between the auxiliary reservoir and the brake cylinder device, and said mervoir-isxrecharged with fluid under pressure mm the brake pipe; and the brake cylinder device ismpenedto the atmosphere for releasing .the brakes. Also with the parts OI the'service portion 3 returned to their normal position, communication is :open between the auxiliary reservoir and the emergency reservoir to allow chargingof the latter to the brake pipe pressure.

. A-mere complete description of the AB valve is not deemed essential to aclear understanding of. the invention but if .further information les to the functioning ofithe AB" valve is desired, reference-may be had to Clyde C. Farmer, Patent --No. 2,031,213, issued February 18, 1936; w

I ll's'cription Brake' releasing valve device 8' The brake releasing valve device 8 comprises 'a casing 58, which is preferably mounted on the pipe bracket 2 and is provided with passages :which form extensions of the passages I5, 21b,

.28 and 2'! in the pipe bracket and are connected action chamber 35.

The casing 60 is also provided with a valve chamber .18 which is in constantopen communication with the brake pipe l2 by way of a passage and branch pipe 1|. Contained in this chamber .is a slide valve 12 which is mounted between two spacedshoulders on a stem 13 which is connected to one side of a'fiexible diaphragm H clamped around its periphery in the casing. Engaging a diaphragm follower at the opposite side of .the

.diaphragm I4 is a push rod 15 mounted-to slide inasuitable bore through the casing and a chamher at this side of the diaphragm is in constant open communication with a passage 16 which leads to' the seat for the slide valve 12 by way of a chamber 85 and a passage 16a.

The push rod is provided for manual operation to deflect the diaphragm H and to move the .slide valve 12 from a, normal position, .in

which it is shown in the drawing, in the direction of the right-hand to a second position de- .fined by a stop shoulder 18 provided on stem 13 engaging a stop or lock member IQ-constituting apart of a stop mechanism 80 hereinafter de- For deflecting the diaphragm 14 .to

scribed. thereby effect movement-of the slide valve 12 into this second position the outerend-of the push rod 15 may be connected by any conventional means (not shown) to opposite sides of a car for operation by a trai-nman.

A rockable strut 8| having one end incontact with the casing within a recess extends through a suitable slot in the diaphragm stem and into a recess in the slide valve 12 wherein it has rocking engagement with said slide valve. This strut is provided with a collar 82 between which collar and the casing is interposed a spring 83 which acts through the medium of the strut to hold "the slide valve seated at all times.

.The stop mechanism 80 hereinbefore mentioned is contained in the-casing 60 and comcommunication with the passages 16 and 16a.

*At the opposite or lower side of this diaphragm .respectively.

thereis a chamberwhich is in constantopen communication with the valve chamber 10 by way of a passage 81. Connected to the lower sideof the diaphragm 84 is a diaphragm follower 88 to which the stop or lock member 19 is attached, .which member is suitably guided in the casing and-provided with an opening through which the diaphragm stem 73 extends. Contained in chamber. and interposed between and operatively engaging the diaphragm follower 88 and the casing is a spring 90 which tends at alltime to urge the diaphragm 84 and attached member IE!v to their stop position, in which position they are shown in the drawing.

When the brake pipe 12 is charged with fluid under. pressure, such pressure efl'ective in valve chamber" on the right-hand face of diaphragm 74 maintains the diaphragm l4 and the slide valve 12 in their normal position in which they are shown in the drawing unless manually moved by the push rod 15 as will be later described.

In this normal position of slide valve 12, passage 65 is open to valve chamber 10 thus connecting brake pipe I2 to passage I3 in the pipe bracket of the AB? valve so that said valve may operate in response to variations in pressure in the brake pipe toapply and release the brakes in the usual manner as above described without any interference from the releasing. valve device 8.

If .a car provided with the brake releasing valve device 8 is cut out of a train and thebrake pipe ,I 2 is vented to the atmosphere in the usualmanner, the AB valve will operate to cause an emergency application of the brakes in the same manner as above described, it being noted that the piston chambers I l and 33 will both be opened tothe vented brake pipe l2 by way of passage l3,

past the slide valve 12 and thence throughvalve chamber 10 and passage and pipe 1|.

vWith thebrakes on the car thus applied and the brake pipe I2 and thereby piston chambers ll To accomplish this a trainman from a position at the side of the car will push the plunger-l5 "position, communication between passage 65 and closed and passage 65 is connected through a chamber 10 and thereby the brake pipe |2 is from the auxiliary reservoir 5 and thereby from the connected brake cylinder to the service and emergency piston chambers II and 33. When due to this flow, a slight increase in pressure is attainedin chamber 33 at one side of the emergency piston 32, the opposite side of which is at munication is closed between the emergency reservoir.6, and the auxiliary reservoir 5 and the brake cylinder device "I. In this position, the feed port 38 is opened to the piston chamber 33 to permit flow of fluid from said chamber to valve chamber 34 and the connected quick action chamber 35. The supply communication leading from the auxiliary reservoir and brake cylinder to the piston chamber 33 have a flow capacity exceeding that of the feed port 38, so as to thereby provide a more rapid increase in pressure in piston chamber 33 than is obtained in valve chamber 34. As a result, a differential in pressure will be created on the emergency piston 32 and when this differential is increased to about ten pounds, said piston will act to position the slide valve 36 in the back-dump position above described, movement of the piston being opposed by the spring weighted plunger 5|. Fluid under pressure will then flow from the auxiliary reservoir 6 and brake cylinder device I through cavity 41 in the slide valve 36 and thence past check valves 55 to passage 56 and into the connected piston chambers II and 33, thereby providing a relatively rapid increase in pressure in said chambers to about fifty-five pounds, thus equalizing the pressure of fluid in the auxiliary reservoir, brake cylinder and chambers Il and 33. .This increase in pressure in piston chambers H and 33 is greater than in the'usual back-dump operation of the AB valve due to the brake pipe l2 on the car being disconnected atthis time from said chambers by the slide valve 12 of the releasing valve device 8. 1

After this back-dump operation, fluid under pressure continues to flow from the emergency piston chamber 33 through feed groove 38 tovalve chamber 34 and quick action chamber 35 for charging same. When the opposing pressures on the emergency piston 32 becomes substantially equal, the pressure of spring 52 acting on plunger 5| will return the piston 32 and associated slide valves to the position in which they are shown in the drawing. It will be noted that during this time the service piston l0 remains in its application position in sealing engagement with the gasket 28 since the auxiliary reservoir pressure efiective in valve chamber I4 is at least equal to the opposing pressure (fifty-five pounds) now in chamber ll.

With the passages 66 and-16a. connected, fluid under pressure supplied to quick action chamber 35 flows by way of passages 61 and S6, cavity 93 in the slide valve 12 and passage 16a to the chamber-85 above the diaphragm 84 in the stop mechanism 80, and from chamber 85 fluid under pressure flows through passage 16 to the chamber at the outer face of diaphragm 14. When the pressure of fluid thus supplied to chamber 85 has been increased to about forty-five pounds, the diaphragm .84 will deflect downwardly against the opposing pressure of the spring 93. Downward deflection of the diaphragm causes the diaphragm follower and attached member 19 to move in the same direction until brought to a stop by the engagement of the follower 88 with a stop I00 provided in the casing. With the follower. in this position, the member 19 will be moved out of engagement with the shoulder 18 on the stem 13. Upon such. movement of the member 19, the pressure of fluid effective in the cham-, her at the outer face of thediaphragm 14, the opposite side of which is at this time subject to atmospheric pressure due to the open communication from the chamber to the brake pipe by way of passage and pipe I l, causes said diaphragm to deflect further in a direction toward the righthand. This furtherdeflection of the diaphragm 14 causes the attached stem '13 and slide valve 12 to move in the same direction until brought to a stop by the engagement, of a follower Illl, attached to the diaphragm, with a stop 102 on the casing. I

With the slide valve in this osition, communication between passages 65 and i5 is closed and passage 65 is connected through cavity 92 to the v passage 2 lb which is connected to the emergency reservoir 6. The cavity 93 in the slide valve maintains the passages 66 and 16a. connected. With communication between passage 65 and Ho established, fluidunder pressure in the emergency reservoir which at this time is substantially sixty pounds will flowby way of passage Zlb; cavity 92 in the slide valve 12 and passages 65 and: i3 to the piston chambers 33 and II thereby effecting an increase in the pressure in said chambers. The resulting increase in pressure in chamber 33, is immaterial, but the increase in pressure in chamber l l on the service piston I0 is of a degree sufliciently in excess of the auxiliary reservoir pressure in chamber H at theopposite side of the piston H) as to cause said piston and slide valves H and I8 to return to their release position for thereby disconnecting therauxiliary reservoir 5 from the brake cylinder device 7 and for opening said brake cylinder device to the atmosphere.

.. Both the auxiliary and emergency reservoirs are thereby disconnected from the brake cylinder device and said device is opened to the atmosphere, thus providing for a release of the brakes on the car without losing the stored fluid pressure in said reservoirs.

, When the car is subsequently cut into a train and the brake pipe I2 is again charged with fluid under pressure, the pressure in valve chamber 10 of the release valve device 8 will increase with that in the brake pipe l2, and when this pressure acting on diaphragm H has been increased to a degree slightly exceeding the pressure of fluid in the quick action chamber 35 and acting on the opposite side of diaphragm 1-4, the diaphragm l4 and thereby the slide valve 12 will be returned to their-normal positions. -With the slidevalve in its normal position, in which position it is shown in the drawing, the passage 66 and thereby the quick action chamber 35 is disconnected from the passage 19a, and, passage 16a is connected to the atmosphere through cavity 93 in the slide valve 12 and an atmospheric passage I05. With the passage 16 thus connected to the atmosphere the pressure of fluid in connected the brake pipe 12 so that the AB" valve will again operate in response to variations in pressure in the usual manner above described.

It will be noted that when the brake pipe I2 is being recharged, movement of diaphra m I4 and slide valve 12 to their normal position'is delayed until such time as the brake pipe pressure in chamber 10 and acting on one side of the diaphragm is increased to a degree exceedingthepressure of fluid atquickaction chamber pressure acting on the other side of the diaphragm. This delay will prevent a reduction in the pressure of fluid" in the emergency piston chamber 33 and thereby insure against unwanted movement of the emergency piston 32 and associated slidevalves to their emergency position in which the auxiliary and emergency reservoir are connected to the brake'cylinder device. That such a reduction would occur if the brake releasingdevice 8. responded immediately to a slight increase in brake pipe pressure is obvious since the fluid at higher ressure in chamber 33 would flow back to the brake pipe which would not yetbe charged to a pressure equal-to the pressure of fluid in the chamber. This delay is attained by maintaining the outer face oidiaphragm It in the release valve connected to. the: quick action champ bet so asto-hold the diaphragm It and slide valve- 12 against-movement: from its brake release posi tion until the brake pipe. pressure increased to a degree exceeding-the pressure bottled up in said; quick action chamber and eonneeted aux- Him. and emergency reservoirs. l

The: parts oi the brake releasing valve device 8 will nowremainin the position inwhich they are showneven though the pressure of fluid inthe brake pipe I2. is reduced to atmospheric pressure asin effecting an emergency application of brakes.

Movement of diaphragm 14 and slide valve It out of their normal: position to their second position defined. by contact or the shoulder T8 with the member-lit mustbe effected manually by rod 15 and. movement to saidthird positiorrwill auto-- matically result upon a given increasein pressure in the quick action chamber 35. Theparts will then remain in this: brake release positionuntil such. time as the recharging of the. brake pipe and valve chamber 10* is being" effectedwith-the car again out into'a train.--

when the caris cut into the train and the-piston chamber H1 and are reconnectedl to the brakepipe it past slidevalve- M, the air required fromthebrake-pipe I 2 for recharging the brake equip. ment is limited to that needed to increase the pressure of fluidin the-auxiliary andtemergency reservoirs from the degree retained therein by;

the brake releasing valve device- & to the normal degree carried in the brake-v pipe thus requiring less fluid pressure and lesstimefor-recharging the system than is ordinarily required wherethe two reservoirs are completely-vented for obtaining a release. otbrakes. a v v Summary From theforegoi-ng descripti'omit will. be a.p.-. parent that. when a car iszsct outofi a. train. the. brake pipe, will be at. atmospheric; pressure; and thefiuid pressurebrakes; will beapplied and that; to release the. brakes. without. loss of the. Stored. fluid pressure in the auxiliary and. emergency reservoirs. oil the.v equipment. all. that. is required. is for a trainman to manually operate thebrake. releasing valve deviceto its brakecylinder venting position. ltzwill also be apparentthot when. the cars again out intoa tr-aim and thc charging of: the brake pipe occurs: the equipment will beautomatically: reset to. provide fcr the usual. well known operationeat the ABf:.equipment tOzCOIltrol the application and release. of" the: brakes..

Having, now; described my invention, what. I

claim as new and desire to secure by Letters Pat ent is:

1. In a fluid pressure brakeequipment of the type comprising a brake pipe normally charged with fluid under pressure; an auxiliary reservoir and an emergency reservoir bothnormally charged with fluid under pressure, a brake cylin-. der, and a brake controlling valve device responsive to a reduction in brake pipe pressure to supply fluid under pressure from both of said reservoirs-to. said brake cyllnder'to effect an application of the. brakes, and responsive to an increase in brake pipe pressure to isolate said reservolrsirom the brake cylinder and to vent fluid under pressure from the brake cylinder to eflect the release or the brakes, In combination, brake releasing control means: interposed in the connection between. the brake pipe and the brake-controlling valve device .and operative to apositionto isolate the brake pipe irom the brake controlling valve device and .to supply fluid under pressure trom said auxiliary reservoir and brake cylinder to the brake controlling valve device to eflect the operation of the device to isolate the emergency reservoir from said auxiliary reservoir and brake cylinder and operative by fluid under pressure supplied. from the auxiliary reservoir and brake cylinder to the brake controlling valve device to another position for supplying fluid under pres; sure from the emergency reservoir" to the brake controlling valve device to eflect the operation 01' the device to vent fluid under pressure-from the brake cylinder to elfect a releaseof the broken. 2.. In. a fluid pressurebralte equipment of the type comprising a brake pipe normally charged with fluid: under pressurei-anauxiliary reservoir and an emergency reservoir both: normally charged with fluidlund'er' pressure; a brake-cylinder, and abrake controlling valve device responsivetoa reduction lIt'bl'NiB-PUPE pressure to supply fluid under pressure from both oi said res ervoirs: to saidibrahe. cylinder to eilect an appllcation of the brakes, and responsive to: an in-' crease in brake. ptpe. pressure to isolate sold reservol-rsfrom: the brake cylinder and to'ventfiuld under pressure. from the brake cylinder to elect the release oil the brakes, in combination, brakereleasing control means operative: manually to a position to: isolate the brake pipe from the brake controlling valve. device and to Supp y fluid under pressurefirom. said auxiliary-reservoir and brake cylinder to-the. brake controlling: valve device-to effect the operation of the device toisolate the. emergency reservoir from saidauxiliary reservoir and brake. cylinder and opemtlve'by fluid RF- der pressure; supplied from. the. auxiliary" reservoir; and brake cylinder. to. the: brake controlling valve. device: to another podtion for supplying fluid under pressure fu'om. the emevpemcy'res envoir to the brake controlling; valve device. to. effect. the operation] of the device to vent: fluid,- under. pressure from the; brake cylinder to.- elect: a release ofjthe hnakeaand delay: means-ion or laying operation 01' said brake. releasing control to said. other position until thefluld under: pressure. supplied. to; the. brake: controlling. valve device from said; auxiliary reservoir: amt. brake cylinder has; been. increasedi above 8.. chosen value.

l 3.. Im a. fluid pressure. brake: equlpmentoi'the type, comprising a; brake pipe. normally charged with fluid. under pressure, an. auxiliaryresenvoir and. an emergency reservoir bothnormally charged-withfluid underpressure; a brake cylinder', and a brake controlling valve device responsive to a reduction in brake pipe pressure to supply fluid under pressure from both ,of said reservoirs to said brake cylinder to efiect an application of the brakes, and responsive to an increase in brake pipe pressure to isolate said reservoirs from the brake cylinder and to vent fluid under pressure from the brake cylinder to effect the release of the brakes, in combination, brake releasing control means operative manually to a position to isolate the brake pipe from the brake controlling valve device and to supply fluid under pressure from said auxiliary reservoir and brake cylinder to the brake controlling valve device to effect the operation of the device to isolate the emergency reservoir from said auxiliary reservoir and brake cylinder and operative by fluid under pressure supplied from the auxiliary reservoir and brake cylinder to the brake controlling valve device to another position for supplying fluid underpressure from the emergency reservoir to the brake controlling valve device to effect the operation of the device to vent fluid under pressure from the brake cylinder to effect a release of the brakes, locking means for locking said brake releasing control means against operation to said other'position, and means responsive to a predetermined increase in the pressure of fluid supplied to said brake controlling valve device from said auxiliary reservoir and brake cylinder to effect operation of said locking means to unlock said brake releasing control means.

4. In a fluid pressure brake equipment of the type comprising a brake pipe normally charged with fluid under pressure, an auxiliary reservoir and an emergency reservoir both normally charged with fluid under pressure, a brake cylinder, and a brake controlling valve device re-' sponsive to a reduction in brake pipe pressure to supply fluid under pressure from both of said reservoirs to said brake cylinder to effect an application of the brakes, and responsive to an, increase in brake pipe pressure to isolate said reservoirs from the brake cylinder and to vent fluid under pressure from the brake cylinder to effect the release of the brakes, in combination, brake releasing control means operative manually to a position to isolate the brake-pipe from the brake controlling valve device and to supply fluid under pressure from said auxiliary reservoir and brake cylinder to the brake controlling valve device to effect the operation of the device to isolate the emergency reservoir from said auxiliary reservoir and brake cylinder and operative by fluid under pressure supplied from the auxiliary reservoir and brake cylinder to the brake controlling valve device to another position for supplying fluid under pressure from the emergency reservoir to the brake controlling valve device to effect the operation of the device to vent fluid under pressure from the brake cylinder to effect a release of the brakes, spring means for locking said brake releasing control means'in its first mentioned position, and movable abutment means operative upon a predetermined increase in the pressure of fluid supplied to said brake controlling valve device from said auxiliary reservoir and brake cylinder to effect operation of said spring means for unlocking said brak re.- leasing control means.

5. In a fluid pressure brake equipment of the type comprising a brake pipe normally charged with fluid under pressure, an auxiliary reservoir and an emergency reservoir both normally charged with fluid under pressure, a brake-cyl-' inder, and,- a brake controlling valve device reervoirs from the brake cylinder and to ventzfluid under pressure from the brake. cylinder to effect the release of the brakes, in combination, a brakereleasing valve device including a slide valve 010- erative manually to a position to supply fluid under pressure from said auxiliary reservoir. to

the brake controlling valve device to effect the operation of said brake controlling valvedevice' to' isolate the emergency reservoir from the auxiliary reservoir and brake cylindensaid slidevalvebeing operative by fluid under pressure suppliedfromthe auxiliary reservoir to the brake controllin valve device to anotherposition for admit? ting fluid under pressure from the emergency reservoir to the brake controlling valve device toeffect the operation of the brake controllingvalvel device to maintain theemergency reservoirs iso-= lated from the brake cylinder and to vent fluid underpressure from the brake cylinder to eifec a release of the brakes. v

6. In a fluid pressure brake equipment of the type comprising a brake pipe normally charged with fluid under pressure, an auxiliary reservoir and an emergency reservoir .both normally.

charged with fluid under pressure, a brake cylinder, and a brake controllingvalve device responsive to a reduction in brake pipe pressure to.

supply fluid under pressure from both of said reservoirs to said brake cylinder to effect an application of the brakes, andresponsive to an in-,

crease in brake pipe'pressure to isolate said res--v ervoirs from the brake cylinder and, to vent fluid under pressure from the brake cylinder to effect the release of the brakes, in combination, a slide valve operative to one position to isolate the brake pipe from the brake controlling valve de-' vice and to supply fluid under pressure from said auxiliary reservoir and brake cylinder to the brake controllin valve device to effect'the operation of the device to isolate the emergency reservoir from said auxiliary reservoir and brake cylinder, and to another position for-supplying for delaying operation of the last mentioned means until the pressure of fluid supplied thereto has been increased above a chosen value.

7. In-a fluid pressure brake equipment of the type comprising a brake pipe; an auxiliary reservoir; an emergency reservoir; and a brake cylinder; in combination, a brake controlling valve device; a passage connecting said brake pipe tosaid brake controlling valve device; said brake controlling valve device being operable upon a reduction in pressure in said passage to open communication between said auxiliary and said emergency reservoirs and thebrake cylinder to efiect an application of the brakes; a release control valve having a normal position, a second position and a third position; said release valve being operative in said normal position for open,-

sponsive to a reductionlinl brake pipe pressure I to supply fluid underpressure from both of said reservoirs to said brake cylinder'to effect-an 'ap-- plicationof the brakes and responsive to an increasein brake pipe pressure-to isolate said-res-:

in said passage to said brake" pipe and being operative in said second position iorclosin: communication between said. brake: pipe and passage and for supplying fluid under pressure. from; said brake cylinder and said auxiliary reservoir to said passage to effect operation of said brake controlling valve device to cut. off the supply 0! fluid under pressure from said emergency reservoir to. said brake cylinder, being operative incsaicl third position for supplying. fluid under pressure from said. emergency reservoir tosaid passage to effect operation of said brake controlling valve device toopen said brake cylinder to the atmosphere to eilect. a. release. at the brakes, and meansfor. controlling. the: positioning of. saidrelease control valve.

ii. In a fluid pressure brake equipment. of. the type comprising a brake pipe; anauxiliary reservoir; an emergency reservoir; and a brake cylinder: in combination. a brake controlling valve device; a passage connecting said brake pipe to- .said. brake. controlling. valve device; said: brake controlling. valve device beingoperable. upon a reduction in pressure irrsaid passage to open communication betweensaid auxdiary and saidemergency reservoirs-and the brake cylinder to' effect an application of the brakes; a. release control: valve having a. normal position, a second. position and: a third. position; said release valve being operative in said normal position tor-opening. said passage to' said brake pipe and being operative in said second position for closing communication between said Make Pipe and passage and. for supplying fluidl under. pres:-

sure from said brake; cylinder and said auxiliary reservoir to said. passageto eifectoperatiomoi said.

brake controlling valve device to cut oil. the supply. 0t fluid under pressure from said.- emergency reservoir to said brake cylinder, and being operative in said third. position for supplying fluidunder pressure from: said emergency reservoir. to; saidpassageto effectv operation of. said brake:c0n trolling valve device-toropen said brake cylinder to the atmosphere'to effect a. release of the brake and means for controlling the positioning or said release control valve; sai means comprising a: manually operative member. for effecting, movement oi. said releasecontrol valve from said nor mal position tosaidsecond position, and fluid pressure responsive means for effecting movement oi. said release: control valve from saidsecond position to said: third: position.

9. In a fluid pressure brake equ pment of. the type; comprising a brake pipe; an auxiliary reservoir; an: emergency reservoir; and a brake cylin-' der; in combination, a brake controlling valve device; a passage connecting said brake pipe to said brake controlling valve device; said brake controlling valve device being operable upon a reduction; in pressure in said passage to open. communication between said auxiliary and. said" emergency reservoirs and. the brake cylinder to eifect an application of: thebrakesg. a release controlzvalve having a normal position, B'SBCODdrDOSi t-ionand a third.- position; said release valve be.-- ing operative in said; normal position. for openin said passage to. said brake ptpe-andbeingoperativeirr said second position for closing communication between saidbrake pipe and passage and for supplying fluid under pressure from saidbrake cylinder and saidauxiliary reservoir tosai'd pas-- sage-to effect operation of said brake controlling valve device tocut air the supply of fluid under pressure from said emergencyreservoir tosaid brake cylinder, and opcrativeinsaid third:

asvasza osition for supplying fluid under ressure. from said emergency reservoir to said passage to elect operation of said brakecontrolling valve device to open said bra-kc cylinder tothe. atmosphere to: effect a release of. the brakes. a manually 0perable: member for effecting movement of said release control valve from said normal position to said second. position; a chamber; and movable abutment means subject to the. opposing pressures offluid in said brake pipe and said chamber operative upon: a decrease in brake pipe pressure and an. in pressure in said chamber for effecting. movement of said release control valve from said second position to said third position.

10.. In a, fluid pressure brake equipment of the type comprising a brakepipe; an auxiliary reservoir; an emergency reservoir; and a brake cylim der; in combination, a brake controlling valve device; a passage connecting said brake pipe to-said. brakecontrolling valve device; said brake controlling valve device being operable upon a reductiontin pressure in said passage to open communication between said auxiliary and said emergency reservoirs and the brake cylinder to effect an application of the brakes; a release control valve. having a normal position, a second position and a third position; said release valve being operative. in said normal position for opening said passaae to said brake pipe and being operative in said second position 'for closing communication between said brake pipe and passage and for supplying fluid under pressure from said brake cylinder and said auxiliary reservoir to said pissage to eifect operation of. said brake controlling, valve device to cut. off the supply of fluid under pressure from said. emergency reservoir to said.

brake cylinder, and. being operative in said third position for supplying fluid under pressure from said emergency reservoir to Said passageto. efiect operation of said brake controlling valve: device to open said brake cylinder to the atmosphere. to effect a release of. the brakes,.a manually operable member tor effecting movement of. said release control valve from said normal position to said second position; a chamber; and movable abutment. means including a. flexible diaphragm subject to the opposing. pressures of fluid inlaid brake. pipe and. said. chamber operable by brake pipe pressure to actuate said: release control valve toitsnormalposition, operablemanually to actuate said. release control valve from said normal position to said. second position and. operable by the pressure of fluid in said chamber to actuate saidrelease control valve from second position to said. third. position.

11.. In a fluid pressure brake equipment of the type comprising a brake pipe; an auxiliary reservoir; an. emergency reservoir; and a brake. cylinder; in combination, a brake controlling valve device; a passage connecting said brake pipe to said brake controlling valve device; said brake controlling valve device being operable upon. a. reduction in pressure. in said passage. to open communication between said auxiliary and said emergency reservoirs and the brake cylinder to eii'ect an application of. the brakes; a release control valve having a normal position, a second position. and: a third position; said release valve controlling valve device to cut off the supply of fluid under pressure from said emergency reservoir to said brake cylinder, and being operative in said third position for supplying fluid under pressure from said emergency reservoir to said passage to effect operation of said brake controlling valve device toopen said brake cylinder to the atmosphere to efiect a release of the brakes, means comprising a manually operable member for eilecting movement of said release control valve from said normal position to said second position, and fluid pressure responsive means for effecting movement of said release control valve from said second position to said third position; a chamber, and means operative to maintain said release valve in said second position, so long as the pressure in said chamber is not increased above a chosen value.

12. In a fluid pressure brake equipment of the type comprising a brake pipe; an auxiliary reservoir; an emergency reservoir; and a brake cylinder, in combination, a brake controlling valve device; a passage connecting said brake pipe to said brake controlling valve device; said brake controlling valve device being operable upon a reduction in pressure in said passage to open communication between said auxiliary and said emergency reservoirs and the brake cylinder to effect an application of the brakes; a release control valve having a normal position, a second position and a third position; said release valve being operative in said normal positionfor opening said passage to said brake pipe and being operative in said second position for closing communication between said brake pipe and passage and for supplying fluid under pressure from said brake cylinder and said auxiliary reservoir to said passage to eflect operation of said brake controlling valve device to cut ofi the supply of fluid under pressure from said emergency reservoir to said brake cylinder, and being operative in said third position for supplying fluid under pressure from said emergency reservoir to said passage to effect operation of said brake controlling valve device to open said brake cylinder to the atmosphere to effect a release of the brakes, means comprising a manually operable member for efiecting movement of 'said release control valve from said normal position to said second position and fluid pressure responsive means for effecting movement of said release control valve from said second position to said third position; a chamber; and means including a locking member operative. to delay movement of said valve from said second position to said third position until the pressure of fluid in said chamber has been increased to a chosen value.

13. In a fluid pres-sure brake equipment of the type comprising a brake pipe; an auxiliary reservoir; an emergency reservoir; and a brake cylinder; in combination, a brake controlling valve device of the type comprising a service portion and an emergency portion; a passage connecting said brake pipe to said brake controlling valve device; said service portion being operable upon a reduction in pressure in said passage to open communication between said auxiliary reservoir and the brake cylinder and said emergency portion being operable upon a reduction in pressure in said passage to open communication between said emergency reservoir and-the brake cylinder to effect an application of the brakes; a chamber; a release valve having a normal position, a second position and a third position; said release valve being operative in said normal position for opening said passage to said brake pipe,

and operative in said second position-for closing communication between said brake pipe and passageand for supplying fluid under pressure to said chamber, and for supplying fluid under.

pressure to said passage to effect operation of said emergency portion to cut off the supply of fluid under pressure from said emergency reservoir to the brake cylinder, and operative in said third position for supplying fluid under pressure from said emergency reservoir to said passage to effect operation of said service portion to open said brake cylinder to the atmosphere to effect a release of the brakes: means comprising a manually operative member for effecting movement of said release valve from said normal position to said second position and fluid pressure responsive means automatically operative for effecting movement of said release valve from said second position to said third position, and locking means operative to lock said release valve in its second position until the pressure of fluid in said chamber is increased to a predetermined value.

14. In a fluid pressure brake equipment of the type comprising a brake pipe; an auxiliary reservoir; an emergency reservoir; and a brake cylinder, in combination, a brake controlling valve device of the type comprising a service portion and an emergency portion; a passage connecting said brake pipe to said brake controlling valve device; said service portion being operable upon a reduction in pressure in said passage to open communication between said auxiliary res- .ervoir and the brake cylinder and said emergency portion being operable upon a reduction in pressure in said passage to open communication between said emergency reservoir and the brake cylinder to eflect an application of the brakes; a chamber; a release valve having a normal position, a second position and a third position; said release valve being operative in said normal position for opening said passage to said brake pipe, and operative in said second position for closing communication between said brake pipe 'and passage and for supplying fluid under pressure to said chamber, and for supplying fluid under pressure to said passage to efiect operation of said emergency portion to cut off the supply of fluid under pressure from said emergency reservoir to the brake cylinder, and operative in said third position for supplying fluid under pressure from said emergency reservoir to said passage to efiect operation of said service portion to open said brake cylinder to the atmosphere to-efiect a release of the brakes, manually operative means for effecting movement of said release valve from said normal position to said second position, fluid pressure responsive means automatically operative for effecting movement of said release valve from said second to said third position, and means for delaying the operation of said fluid pressure responsive means until the pressure of fluid in said'chamber is increased to a chosen value.

RALPH T. WHITNEY. 

